On Ubuntu 10.4 I have edited the /etc/bash.bashrc file to set some variables like the command history size (HISTSIZE=5000), however if I create a new users Ubuntu by default gives them a .bashrc file in their home directory with this set as HISTSIZE=1000 which is overriding mine. How can I change the default .bashrc file that is created?

If you want to set this up proactively, tell the .bashrc file in /etc/skel/ to source, for instance, /etc/defaults/bashrc or whatever file you choose. That still won't prevent users from removing the line in their own .bashrc if they want it gone, but.
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ShadurDec 12 '11 at 7:54